A fluorescence measuring apparatus is known which acquires information about an object to be measured by irradiating the object to be measured with laser light and receiving fluorescence emitted from the object to be measured.
A flow cytometer using such a fluorescence measuring apparatus can acquire information per object to be measured by allowing objects to be measured such as cells, DNAs, RNAs, enzymes, or proteins labeled with a fluorochrome to flow in a sheath fluid, irradiating the objects to be measured with laser light, and measuring fluorescence emitted from the fluorochrome labeling the objects to be measured.
Further, another fluorescence measuring apparatus is known which acquires a fluorescence relaxation time constant by irradiating an object to be measured with laser light whose intensity is modulated at a predetermined frequency and receiving fluorescence emitted from the object to be measured (Patent Document 1).